Method and apparatus for raising liquids by compressed air.



No. 857,768. PATENTED JUNE 25, 1907. R. STIRLING. METHOD AND APPARATUSFOR RAISING LIQUIDS BY GOMPRBSSED AIR.

APPLICATION FILED JUNE 20.1905.

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i.) [LLJQJ- //v VENTO/Q A A4- M Aa/L W/ rA/ESSES fom PATENTRD JUNE 25,1907,

R. STIRLING. METHOD AND APPARATUS FOR RAISING LIQUIDS BY COMPRESSED AIR.

APPLICATION FILED JUNE 20,1905.

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PATENTED JUNE 25, 190'?.

R. STIRLING. METHOD AND APPARATUS POR RAISING LIQUIDS BY GOMPRESSED AIR.

APPLICATION FILED JUNE 20.1905.

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ROBERT STERLING,- or IsURRET, ENGLAND. METHOD ANaAPPAR/uus Foa msm@uoums Y coMPRrssEn Am.

Speccatoli of Letters Patent.

Application filed Tune 20,1905. Serial No. 266,181. f

.To aZZ whom it may concer/t:

Be it known that I, ROBERT STIRLING, of

The Anchorage, Dormans Park, Surrey, England, engineer, have invented acertain new and useful Improved Method and Apparatus for Raising Liquidsby Compressed Air,` of which the following is a specification.

This invention relates to apparatus for raising liquids by compressedair.

The object of the invention is to provide an apparatus which will workefhciently and 'economically in deep wells generally, and in wells wherethe surface of the liquid is at a considerable depth below the surfaceof the ground andthe depth of the liquid Small in comparison therewith.

Various means have been tried with a view to improving the eiiiciency ofliquid-raising apparatus of the air-lift type. It has heretofore beenproposed to so form the air and liquid inlets to the discharge pipepasto obtain, under given conditions, the maximum;

mergence -was not attainable, or, in othery words, when the ratio of thedistance of the .nozzle below the surface of the liquid was to thedistance from the surface of the liquid to the discharge much less than-the ratio of 9 to 6, the well was pronounced unsuitable for air-liftpumping.

N ow I have discovered that the efliciency of air-lift apparatus can begreatly improved,

l and a steady and regular discharge obtained,

mately equal to that of the mixture of iq'uid` above the liquid inlet 5oby causing the liquid to enter therising or discharge pipe at a velocitywhich is approxiand air in the discharge pi e. immediately or in ets.The ideal conditions are attained when the velocity of theentering'liquid is precisely lthe same as that of the mixture above it,but I have found in practice that these conditions may be somewhatwidely departed from while still obtaining to a greater or less degreethe advantages of my invention. The speed of the entering liquid may besomewhat below that of the mixture, or it may be considerably above thespeed of the mixture and important results still be obtained. I havefound in practice that the velocity of the entering liquid may be2 or 3times that of the mixture with good results, while if raised materiallybeyond this speed the efficiency of the apparatus decreases, while withthe inlet speed 8 o'r 10 times the speed of the mixture,`

as in the ap aratus hereinbefore referred to, a considerabll Thesevariations in relative speed whi'ch lie within the scope lof myinvention are intended` to be included, for the Want of a better term,in the phrase approximately equal .to the velocity of the mixture, orany phrase of like import used herein. Generally I have found thatsatisfactory results are obtained` when the parts are so proportionedthat the velocity of the entering'liquid is not greater than that whichwould be ue to a head of 10 per cent. of the submergence. In otherwords, the entering liquids given the velocity which it would have 1fpermitted to flow unimpeded into a pipel the end of which was submerged1/10 'of .the actual degree of submergence in practice. Under theseconditions a considerably greater speed is given to the liquid than tothe mixture. This is advanta eous, as the level of the Water in a givenWe l is apt to vary greatly, and When at its lowest point the inletspeed is substantially reduced. Such reduction should not carry it`materially below the speed of the mixture.

" An important feature of invention is that the submergence of less than50 per cent. can be worked with greater advantage, the a paratus beingadapted to be placed below tle level of the liquid at a depthwhich bearsa ratio to the depth from the surface of the liquid in the well tothepoint of discharge of less than 4 to 6. Thus a saving is eected dueto length of piping, and to less air pressure being necessary as'theamount of lsubmergence is less, and wells hitherto unsuited for air-liftpumps can be Worked by this means. By myv invention the slip of airthrough mum, and Waste of energy change of speed is obviated.

In practicing my invention I provide a nozzle or nozzles for admittingthe liquid in suitably determined volume and velocity to resulting frome drop in efficiency takes place.

the liquid is reduced to the mini-` Patented June 25, 1907. V

in the material of the piping, in the friction A IIO in and through thenozzle or nozzles equal to,

or approximately equal to, the initial velocity of the mixture of liquidand air 1n the discharge pipe immediately above the nozzle or nozzles.'In other words, the sectional area of the liquid inlet passage orpassages in the nozzle or nozzles bears the same or approximately thesame proportion to the area of the discharge pipe, rising pipe or thelike as the volume of liquid passing through the nozzle or nozzles in agiven time bears to the volume of air and liquid passing through thedischarge pipe or the like immediately above the nozzle or nozzles inthat time.

The compressed air is admitted in the usual or any convenient way to theliquid in the discharge pipe or the like, above the nozzle or nozzlesthrough which the liquid enters. The assage or passages above the nozzleor nozz es for the admission of the compressed air should be of sucharea that little or no resistance is presented to the entering air. v

Referring now to the drawings:-Figure l is a general view of one form ofapparatus made in accordance with this invention, in which the airsupply pipe is outside the discharge pipe. Fig. 2 isa section of theapparatus Showing the air inlet and one liquid inlet nozzle. Fig. 3 isageneral view ofamodified form of apparatus in which the air supply pipeis disposed outside the discharge pipe, Fig. 4 is a section showing anair inlet and one liquid inlet nozzle adapted for use with the generalarrangement shown in Fig. 3. Fig. 5 is a sectional plan thereof. Fig. 6is a general view of a modified form of apparatus in which the airsupply pipe is disposed inside the discharge pipe. Fig. 7 is a sectionshowing the air inlet and the liquid inlet comprising several nozzlesadapted for use with the general arrangement shown in Fig. 6. Fig. 8 isa sectional plan thereof. Fig. 9 is a section showing the constructionof Fig. 2, with the tapered portion omitted.

a is the well in which the apparatus is disposed, .b is the air supplypipe, c the discharge pipe,- d the liquid inlet and comprises one ormore nozzles, e the air inlet and fthe li uid supply pipe.

n operation, the air is forced down on to the surface of the liquid,vand the pressure thereon increases until the level of the liquid `isdepressed sufhciently'to enable the airto get to the air inlet or inletsabove the nozzle. The air then enters below the column of liquid in thedischarge pipe, which is thus partly aerated and discharged. The aircontinues to enter the dischargepipe, and owing to the relativesectional areas of the nozzle inlet and the discharge pipe, the quantityof liquid entering the discharge pipe through the nozzle or nozzles isautomatically regulated by the weight of the laerated column in thedischarge pipe to an extent such that the velocity of this iniiow isequal to or approximately equal to the velocity of the aerated liquid inthe discharge pipe immediately above the nozzle or nozzles, that is tosay, above the tapered portion 76. The inlet area of the nozzle ornozzles is proportioned to this quantity which is predetermined, and canbe readily calculated by known methods and formulae used in designingair lift pumping apparatus, taking into account the quantity of liquidwhich can be economically discharged thrcugh a pipe of-given area, andthe ratio between the quantities of air and liquid depending on theheight of lift andthe depth of submergence. As the inlet is restrictedso that the liquid enters the discharge pipe at the same orapproximately the same velocity as the initial velocity of the mixtureof air and liquid and as the volume is such that it is sufiicientlylightened to form a rising column by the entering air then slip of theair through the liquid is avoided and there is practically no waste ofenergy due to change of speed and the efficiency of the apparatus isestablished. i

The proportions just indicated may be varied considerably withoutdeparting from the invention. Preferably the velocity of the incomingliquid is exactly that of the rising mixture, but as the depth ofsubmergence is a factor in the velocity of the entering liquid, and asthe'height of the water in most wells and hence the degree ofsubmergence is variable, such precise velocities cannot in most cases beattained. Preferably the parts are so proportioned that the speed of theliquid and mixture are equal at the low-water point of the well, so thatwhen the water is above this level the speed of the liquid becomesgreater than that of the mixture. In most cases the variations can beprovided for by proportioning the nozzle so that the velocity of theliquid is not greater than that which would be due to a head of 10 percent of the submergence. i

In theform shown in Figs. l and 2, the discharge pipe c is disposedconcentrically within the compressed air pipe b and only one nozzle isused in the' air inlet d. The pipes l) and f are connected by a socket gprovided with a ledge h adapted to support the discharge pipe c providedwith the air inlet e and the liquid inlet d in such a way thatcommunication between the pipes f and c can only take place through thenozzle d. is a ring of suitable material disposed on the ledge h so asto make this tight joint.

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the air inlet e which is connected to the pipe l) by several smallholes, is of annular form and is directed upwardly into the passage 7c.This passage 7c is vvfor the purpose of providing an easy flow into thedischarge pipe c'. y

In the form shown in Figs. 3 and 4 and 5 the discharge pipe c is outsideand independent of the air pipe 1). The nozzle d is disposed inthesocket g and is surrounded by the upwardly directed air inlet e which isconnected to thc air pipe b by a passage min the socket g.

In the form shown in Figs. 6, 7 and 8 the air pipe b"l passesconcentrically down the discharge pipe c2 and terminates in a headadapted to fit tightly in the pipe czby means of a band n of anysuitable material.- The air inlet is shown at e2. The liquid inlet d2comprises several nozzles which are carried by the head and open intothe annular passage fz at the foot of the discharge pipe c2, thecombined area of said nozzles being equal to the area of 'the singlenozzle proportioned as above described. Similarly several nozzles may besubstituted for a single one in the liquidv inlets of the forms shown inFigs. 1 to 5, the total area of the inlet always being proportioned asabove described.

In each of the forms hereinbefore referred to there is provided atapering portion such as k' 7a2 to permit an easy flow in to the disicharge pipe. Such passage is not necessary and may bc omitted, asisshown in Fig. 9, which is in other respects substantially like the formshown in Fig. 2.

What I claim and desire to secure by Letters Patent is 1. ln the raisingof liquids by compressed air wherein a current of air is introduced intoa discharge pipe which is in communication with the liquid below thelevel of the latter the method which consists in introducing the liquidinto such Apipe atiapproximately the same velocity as that attained bythe up-` wardly moving mixture of liquid and air immediately beyond thepoint of introduction of said liquid.

2. In the raising of liquids by-compressed air wherein a current of airis introduced into a discharge pipe which is in communication with theliquid below the level of the latter, the method which consists in-introducing the liquid into such pipe through a nozzle, the sectionalarea of whichis so restricted with relation to that of said pipe at apointl immediately above such nozzle that the velocity of said liquidpassing said nozzle is approximately equal to that of the mixture of airand liquid passing such point.

3. The method of raising liquid which consists in submerging the end ofa pipe in such liquid, introducing a current of air thereinto at a pointbelow the surface thereof, and relthat its velocity is approximatelystricting the iniiow of liquid into such pipe so equal to that of theupwardly moving current of air and liquid. y

4. In an air lifting apparatus for liquids, va discharge pipe, an airinlet thereto, and aliquid inlet thereto, the cross sectional area ofsaid liquid inlet and said discharge ipe being so proportioned that theHuid) passing 'through said liquid inlet and that. portion of said pipeimmediatelybeyond the same shall move at approximately the samevelocity.

5. In an air lifting apparatusfor liquids, a.

discharge pipe, an air inlet thereto, and a nozzle adapted to introducethe liquid intoy such pipe, said pipe and nozzle having theircross-sectional areas so proportioned that the fluids passing throughsaid nozzle and that portion of said pipe which is immediately beyondthe same shall move at approximately the same velocity.

6. In an apparatus for raising liquid by compressed air wherein acurrent of air is introduced into a discharge pipe which is incommunication with the Vliquid below the level of the latter, adischarge'pipe so proportioned with relation to the liquid inlet thatthe liquid introduced into suchV pipe shall move at approximately thesamev-elocity as that attained by the upwardly moving mixture of liquidand air immediatelybeyond v the air.

7 In the raising of liquids by compressed air wherein a current of airis introduced into a discharge pipe which is in communication with theliquid'below the level of the-latter the method which consists inintroducing the liquid into such 4pipe at a velocity approximately equalto that of the mixture of liquid and air above the liquid inlet, but notgreater than that due to a head of 10%gof submergence.

8. 'In the raising of liquids by compressed air wherein a current of airis introduced. into a discharge pipe which is Ain communication with theliquid below the level of the latter point of introduction of the liquidand the method which consists in introducing the liquid into such pi ethrough anozzle the sectional area of whidh is so restricted withrelation to that of said pipe at al point immediately above such nozzlethat the velocity of said li uid passing said nozzle is not` greaterthan t at dueto a head of 10% of submergence.

9. The method of raising liquid which consists in submer'g'ing the endof. a pipe in such liquid, introducing a current of air thereinto at apoint below the surface thereof, and rstricting the iniiow of liquidinto such pipe so that its velocity is not greater than that due to ahead of 10% of submer ence whereby the velocity'of the entering iquidapproximates that of the mixture above it.

l0. In an air lifting apparatus for liquids, a

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i' to a head of 10% of submergence.

11. In an air lifting apparatus for liquids, a discharge pipe, an airinlet thereto, and a nozzle adapted to introduce the liquid into suchpipe said pipe and nozzle having their cross-sectional areas soproportioned that the fluids passing 4through said nozzle and thatportion of said pipe which is immediately beyond the same shall move ata velocity not greater ythan that due to ahead of of submergence.`

12. In anapparatus Jfor raising liquid by compressed air wherein acurrent of air is introduced into a discharge pipe which is incommunication with the liquid below the level of the latter', adischarge pipe so proportioned with relation to lthe liquid inlet thatthe liquid introduced into such pipe shall move at a velocity notgreater-than that due to a head of 10% of submergence.

13. In the raising of liquids by compressed air wherein a current of airis introduced into a discharge pipe which is in communication with theliquid below the level of the latter, the method which consists inintroducing the liquid into such pipe through a plurality of nozzles thesectional area of which is so restricted with relation to that of saidpipe at a point immediately above such nozzles that Awhich isimmediately beyond the same shall move at approximately the samevelocity.'

15'. In the raising of liquids by compressed air wherein a curre`ntofsa1r is introduced into a discharge pipe which is in communicationwith the liquid below the level of the latter, the method which consistsin introducing the liquid into such pipe through a plurality of nozzlesthe sectional area of which is so restricted with relation to that ofsaid pipe at a point immediately above such nozzles that the velocity ofsaid liquid passing said nozzles is not greater than that due to a headof 10% of submergence.

16. In an air lifting apparatus for liquids, a discharge pipe, an airinlet thereto, and a plurality of nozzles adapted to introduce theliquid into such pipe said pipe and nozzles having their cross-sectionalareas so proportioned that the fluids passing through said nozzles andthat portion of said pipe which is immediately beyond the same shallmove at a velocity not greaterthan that due to a head of 10% ofsubmergence.

17. The combination with a well or the like7 of an air lifting apparatushaving a liquid inlet at a predetermined depth of submergence, and a,discharge pipe for the mixture of air and liquid beyond said inlet,said inlet and discharge pipe immediately beyond said inlet being soproportioned with relation to the depth of submergence that the incomingliquid flows at approximately the same lvelocity as the mixture in suchportion of the discharge pipe.

18. The combination with a well or the like, of an air lifting apparatushaving a discharge pipe, and a nozzle ada ted to introduce liquid intosuch pipe, suc nozzle being arranged at a predetermined depth ofsubmergence, Said pipe and nozzle having their cross-sectional areas soproportioned with relation to the depth of submergence that the incomingliquid flows at approximately the same velocity as the mixture of airand liquid in said discharge pipe immediately beyond said nozzle.

In witness whereof, l have hereunto si ned my name in the presence oftwosubscri ing witnesses.

ROBERT STIRLING. l.llitnessesz REGrNALD EATON ELLIS, ROBERT MILTONS'SPEARPOINT.

